1. Field of the Invention
The field of art to which this invention pertains is the catalytic conversion of hydrocarbons. This invention also relates to hydrocarbon conversion catalysts and their methods of manufacture. The catalyst composite of the present invention demonstrates unexpected and exceptional activity, selectivity and resistance to deactivation when employed in a hydrocarbon conversion process. More particularly, the invention relates to a catalyst which is useful for performing the hydrocracking of hydrocarbons.
2. Description of the Prior Art
The hydrocracking of hydrocarbons by catalytic means is old and well known in the prior art. Hydrocracking of hydrocarbon oil, which may be high-boiling fractions, such as for example reduced crudes, gas as oils, topped crudes, shale oil, coal extract, and tar sand extract, generally is performed at relatively high temperatures and pressures of the order of 500.degree. F. and 500 psig and upward. Catalysts for the hydrocracking of hydrocarbons are generally moderate to strong hydrogenation catalysts.
The prior art hydrocracking catalysts will typically comprise one or more components selected from silica, alumina, silica-alumina, crystalline aluminosilicate, or other refractory inorganic oxides and at least one metal component from Group VIB or Group VIII. Hydrocracking catalysts containing alumina and crystalline alumino-silicate or alumina and silica have been shown to be particularly effective in the hydrocarbon hydrocracking process. One or more hydrogenation components have been selected by the prior art to serve as the hydrogenation component in hydrocarbon conversion catalysts. The prior art has broadly taught that hydrogenation components may be selected from at least the following metals: iron, cobalt, nickel, ruthenium, rhodium, palladium, osmium, iridium, platinum, chromium, molybdenum, tungsten, vanadium, niobium, and tantalum.
In U.S. Pat. No. 3,963,601 (Hilfman), a hydrocarbon conversion catalyst is disclosed which catalyst comprises an alumina-silica support, a Group VIB metal component, a Group VIII metal component and a fluoride component. Additionally, the Hilfman patent discloses and teaches that the final catalyst composite is dried at a temperature from about 200.degree. F. to about 600.degree. F. for a period from about 2 to about 24 hours and finally calcined at a temperature of about 700.degree. F. to about 1100.degree. F. for a period of about 0.5 to about 10 hours.
It is generally recognized that catalysis is a mechanism particularly noted for its unpredictable nature. Minor variations in a method of manufacture often result in an unexpected improvement in the catalyst product with respect to a given hydrocarbon conversion reaction. The improvement may be the result of an undetermined alteration in the physical character and/or composition of the catalyst product difficult to define and apparent only as a result of the unexpected improvement in the catalyst activity, selectivity and/or stability.
One of the discoveries of the present invention is a novel catalyst which exhibits improved and unexpected hydrocarbon conversion characteristics, such as for example activity, selectively and extraordinary stability. The present invention also describes the utilization of the novel catalyst in a hydrocarbon conversion process. Another embodiment of the present invention describes methods for preparing catalysts.